The retinacular arteries play an important role in vascularizing the femoral head. Their role increases in adulthood when epiphyseal cartilage blocks other vessels. Fractures of the femoral neck can disrupt these arteries, putting the head at risk. Both hip implants and resurfacing can also impact the retinacular arteries. Surgeons must consider various design factors for implants as well as potential complications.

1. RETINACULAR
ARTERIES
Rahilla Khatoon, Moza Al-Khulaifa, Irsalan Asif and James
Alexander

2. Overview
 Retinacular arteries
 Role of the retinacular arteries
 Childhood Adult
 Failure
 Treatment
 Surgery
 Complications

3. Vasculature of the femur
1. Illio-femoral artery
2. Ligamentum teres
3. Obturator artery
4. Femoral artery
5. Profunda femoris- 4a. perforating arteries
6. Lateral circumflex femoral artery (LCFA) -
5a. Ascending, 5b. Transverse and
5c.Descending
7. From the ascending – ascending cervical
arteries
8. Subsynovial
9. Medial circumflex artery
Pixgood.com, (2015). Pix For > Medial Circumflex Femoral Artery. [online] Available from: http://pixgood.com/medial-circumflex-femoral-artery.html
[Accessed 19 Mar. 2015].

4. Retinacular arteries
ALPF Medical Research, (2015). Vascular Supply To The Femoral Head. Femoral head. [online] Available from: http//http://www.alpfmedical.info/femoral-head/vascular-supply-to-
the-femoral-head.html [Acessed 17 Mar 2015].

5. The Role
 Vascularise femoral head.
 Lateral retinacular artery –important
 Anastomose at base
 subsynovial interarticular ring.
 Epiphyseal arteries supply head.
Koval, K., & Zuckerman, J. (2000). Hip fractures: a practical guide to management. Springer Science & Business

6. Change in role from childhood to
adulthood.
 LFCA and artery of ligamentum teres
 Posterosuperior lateral epiphyseal and posteroinferior retinacular
branch -4 years
 Metaphyseal vessels < 3 years old, after 14-17years
 14-17 years
 physis blocks metaphyseal.
 anastomoses between metaphyseal-epiphyseal vessels.
Woon, C. (2015). Proximal Femur Fractures - Pediatric - Pediatrics - Orthobullets.com. [online] Orthobullets.com. Available at:
http://www.orthobullets.com/pediatrics/4018/proximal-femur-fractures--pediatric [Accessed 14 Mar. 2015].

7. Change in role from childhood to
adulthood.
 Arteries- intramedullary at neck.
 Anastomose with obturator artery.
 Epiphyseal cartilage prevents retinacular artery
vascularising the head.
Virtual Anatomy Lab: Study notes. (2015). 1st ed. [ebook] Ottawa, p.1. Available at:
http://www.med.uottawa.ca/research/edemonstrator/w1/en/EN-study-notes-week-1.pdf [Accessed 19 Mar. 2015].

8. Causes of failure
 In fractures of the neck of the femur, the fate of the
head depends upon the residual vascularity.
 Blood supply depends wholly on the retinacular and
foveolar vessels.
 Displacement of the fragments is greatest when the
fracture line is vertical, and least when it is more
horizontal.
Ellis H, Mahadevan V. Clinical anatomy. Chichester, West Sussex, UK: Wiley-Blackwell; 2013.
Snell R. Clinical anatomy by systems. Philadelphia: Lippincott Williams & Wilkins; 2007.
Michelson J, Riley L. Considerations in the comparison of cemented and cementless total hip prostheses. The Journal of Arthroplasty. 1989;4(4):327-334.

9. Causes of failure
 The nearer the fracture to the femoral head, the
weaker the retinacular blood supply
 Hip resurfacing can also disrupt the retinacular blood
flow.
 This is because as part of the procedure they
sacrifice a branch of the medial circumflex femoral
artery.
 Depending on how much of the head has lost blood
supply, will determine its salvation.
Ellis H, Mahadevan V. Clinical anatomy. Chichester, West Sussex, UK: Wiley-Blackwell; 2013.
Snell R. Clinical anatomy by systems. Philadelphia: Lippincott Williams & Wilkins; 2007.
Michelson J, Riley L. Considerations in the comparison of cemented and cementless total hip prostheses. The Journal of Arthroplasty. 1989;4(4):327-334.

10. Sorensen L. Wound Healing and Infection in Surgery. Arch Surg. 2012;147(4):373.

11. Polismed.com. Index of /upfiles/other/artgen/134 [Internet]. 2015 [cited 22 March 2015]. Available from:
http://www.polismed.com/upfiles/other/artgen/134/

12. Design considerations of the hip
implant
 Cemented or cement-less hip prosthesis
 Unibody or modular femoral stems
 Material consideration
 Cemented or cementless acetabular component
 Single component acetabular cup or modular cup
 Bearing surfaces
Michelson J, Riley L. Considerations in the comparison of cemented and cementless total hip prostheses. The Journal of Arthroplasty. 1989;4(4):327-334.

13. Hip resurfacing
 Adolescence/minor necrosis
 Bone preservation
 Bone is sculpted to accept a cap/short stem
 Replacement acetabulum needed
 Increased amount of femoral neck fracture
 Heterotopic ossification
Laskin RS, Su EP, Padgett DE. Hip Resurfacing: an Overview [online]. Available from: http://www.hss.edu/conditions_hip-resurfacing-overview.asp#.VQ_lrfmzKG4 [Accessed
14/03/15]

14. Surgical Procedure
 Minimally invasive surgery
 Small incisions (<10cm)
 Acetabulum templating
 Femoral templating
 Size depends on cement/uncement
 Modular
Marya, S. K. S, and R. K Bawari. (2010) Total Hip Replacement Surgery. New Delhi: Jaypee Brothers
Medical

15. Complications
 Wear & corrosion products
 Inflammation
 Infection
 Thrombosis
 Nerve damage
 Loosening
 Leg length discrepancy
Ochsner, P.E. (2003) Total Hip Replacement. Berlin: Springer

16. Clinical case study
 41 years old male.
 Pain killers and anti-inflammatories.
 Radiographs
 chiropractor
 Antalgic limp
Karim, R., & Goel, K. D. (2004). Avascular necrosis of the hip in a 41-year-old male: a case study. The Journal of the
Canadian Chiropractic Association, 48(2), 137.

17. Diagnosis and Treatment
 MRI
 EMG
 Right hip limited motion
 Increased pain in abduction
and internal rotation.
 Cementless total hip
replacement.
Karim, R., & Goel, K. D. (2004). Avascular necrosis of the hip in a 41-year-old male: a case study. The Journal of the
Canadian Chiropractic Association, 48(2), 137.

18. Summary
 Retinacular arteries
 Increasing importance in adulthood
 Femoral neck fractures
 Hip implants
 Surgical considerations
 Complications